Effect of food availability and leptin on the physiology and hypothalamic gene expression of the golden spiny mouse: a desert rodent that does not hoard food

Abstract

Food availability and quality in desert habitats are spatially and temporally unpredictable, and animals face periods of food shortage. The golden spiny mouse (Acomys russatus) is an omnivorous desert rodent that does not hoard food, requiring it to withstand such periods by physiological means alone. In response to food restriction, plasma leptin concentrations, core body temperature, and energy expenditure of the spiny mouse decrease significantly after 24 h, and most spiny mice are able to maintain their body mass to approximately 85% of ad libitum for a prolonged period of time. Both 1-day food deprivation and long-term food restriction had a significant effect on body mass and plasma leptin concentrations, which decreased significantly with a high correlation, as well as on the orexigenic agouti-related protein, which increased significantly as a result of the 24-h food deprivation; and on neuropeptide Y (NPY), in which the increase was more pronounced under long-term food restriction. Food restriction and food deprivation had no effect, however, on the anorexigenic pro-opiomelanocortin and cocaine and amphetamine-related transcript. Leptin administration to food-restricted spiny mice did not affect food intake or the rate of decrease in body mass, indicating that it cannot overcome the drive to eat when food is scarce. However, it did result in a significant decrease in NPY levels, and the spiny mice spent less time at low body temperatures compared with PBS-treated golden spiny mice. These results show that in food-restricted golden spiny mice, leptin affects thermogenesis, but not food consumption, and suggest that the thermoregulatory effects of leptin are mediated by NPY.

Foraging sequence, energy intake and torpor: an individual‐based field study of energy balancing in desert golden spiny mice

“…; Gutman et al . , , ). They do not hoard food, have no cheek pouches and consume mainly animal matter, which is difficult to store; therefore, food foraged is food consumed.…”

“…Golden spiny mice defend their body mass by using torpor during food shortage periods and gain fat mass when food is plentiful (Kronfeld-Schor et al 2000;Ehrhardt et al 2005;Gutman et al 2006Gutman et al , 2007Gutman et al , 2008. They do not hoard food, have no cheek pouches and consume mainly animal matter, which is difficult to store; therefore, food foraged is food consumed.…”

Water deprivation induces appetite and alters metabolic strategy in Notomys alexis : unique mechanisms for water production in the desert

“…There is a report on the appetite regulation in response to food restriction in a desert rodent, the golden spiny mouse, Acomys russatus [31]. Acomys do not store food, unlike Notomys, and thus respond quickly to food restriction.…”

Variation of food availability affects male striped hamsters (Cricetulus barabensis) with different levels of metabolic rate

“…Decreased leptin expression has often been associated with neuroendocrine and neurochemical changes in response to fasting or FD (Ahima et al 1996;Doring et al 1998). For example, food restriction resulted in upregulation of AgRP and NPY in the arcuate nucleus of the hypothalamus associated with decreased leptin expression in striped hamsters , golden spiny mice (Gutman et al 2008) and rats [Rattus norvegicus (Berkenhout, 1769)] (Brady et al 1990;Schwartz et al 1993;de Rijke et al 2005;Johansson et al 2008;Sucajtys-Szulc et al 2008). In the present study, the hypothalamic AgRP showed a marginal increase (P = 0.06) in FD males compared to the control males, which is consistent with previous findings (Wen et al 2018).…”

“…For example, the level of serum leptin (a hormone that is mainly produced by adipocytes and has been implicated in energy expenditure and balance) has been shown to decrease in food-deprived animals (Mercer et al 1998;Schneider et al 2000;Mustonen et al 2008;Speakman & Mitchell 2011;Gao et al 2014) and such decreased serum leptin was associated with decreased fat mass as a result of fasting (Ahima et al 2000). FD also increased hypothalamic gene expression of neuropeptides such as neuropeptide Y (NPY) and agouti-related protein (AgRP) in the golden spiny mouse [Acomys russatus (Wagner, 1840)] (Gutman et al 2008). Interest-ingly, leptin supplement attenuated food restriction-enhanced gene expression of NPY and AgRP in the hypothalamus of striped hamster, indicating that leptin may play a key role in mediating responses to fasting Wen et al 2018).…”